//===-- GDBRemoteRegisterContext.cpp --------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include "GDBRemoteRegisterContext.h"

#include "lldb/Target/ExecutionContext.h"
#include "lldb/Target/Target.h"
#include "lldb/Utility/DataBufferHeap.h"
#include "lldb/Utility/DataExtractor.h"
#include "lldb/Utility/RegisterValue.h"
#include "lldb/Utility/Scalar.h"
#include "lldb/Utility/StreamString.h"
#include "ProcessGDBRemote.h"
#include "ProcessGDBRemoteLog.h"
#include "ThreadGDBRemote.h"
#include "Utility/ARM_DWARF_Registers.h"
#include "Utility/ARM_ehframe_Registers.h"
#include "lldb/Utility/StringExtractorGDBRemote.h"

#include <memory>

using namespace lldb;
using namespace lldb_private;
using namespace lldb_private::process_gdb_remote;

// GDBRemoteRegisterContext constructor
GDBRemoteRegisterContext::GDBRemoteRegisterContext(
    ThreadGDBRemote &thread, uint32_t concrete_frame_idx,
    GDBRemoteDynamicRegisterInfoSP reg_info_sp, bool read_all_at_once,
    bool write_all_at_once)
    : RegisterContext(thread, concrete_frame_idx),
      m_reg_info_sp(std::move(reg_info_sp)), m_reg_valid(), m_reg_data(),
      m_read_all_at_once(read_all_at_once),
      m_write_all_at_once(write_all_at_once), m_gpacket_cached(false) {
  // Resize our vector of bools to contain one bool for every register. We will
  // use these boolean values to know when a register value is valid in
  // m_reg_data.
  m_reg_valid.resize(m_reg_info_sp->GetNumRegisters());

  // Make a heap based buffer that is big enough to store all registers
  DataBufferSP reg_data_sp(
      new DataBufferHeap(m_reg_info_sp->GetRegisterDataByteSize(), 0));
  m_reg_data.SetData(reg_data_sp);
  m_reg_data.SetByteOrder(thread.GetProcess()->GetByteOrder());
}

// Destructor
GDBRemoteRegisterContext::~GDBRemoteRegisterContext() {}

void GDBRemoteRegisterContext::InvalidateAllRegisters() {
  SetAllRegisterValid(false);
}

void GDBRemoteRegisterContext::SetAllRegisterValid(bool b) {
  m_gpacket_cached = b;
  std::vector<bool>::iterator pos, end = m_reg_valid.end();
  for (pos = m_reg_valid.begin(); pos != end; ++pos)
    *pos = b;
}

size_t GDBRemoteRegisterContext::GetRegisterCount() {
  return m_reg_info_sp->GetNumRegisters();
}

const RegisterInfo *
GDBRemoteRegisterContext::GetRegisterInfoAtIndex(size_t reg) {
  RegisterInfo *reg_info = m_reg_info_sp->GetRegisterInfoAtIndex(reg);

  if (reg_info && reg_info->dynamic_size_dwarf_expr_bytes) {
    const ArchSpec &arch = m_thread.GetProcess()->GetTarget().GetArchitecture();
    uint8_t reg_size = UpdateDynamicRegisterSize(arch, reg_info);
    reg_info->byte_size = reg_size;
  }
  return reg_info;
}

size_t GDBRemoteRegisterContext::GetRegisterSetCount() {
  return m_reg_info_sp->GetNumRegisterSets();
}

const RegisterSet *GDBRemoteRegisterContext::GetRegisterSet(size_t reg_set) {
  return m_reg_info_sp->GetRegisterSet(reg_set);
}

bool GDBRemoteRegisterContext::ReadRegister(const RegisterInfo *reg_info,
                                            RegisterValue &value) {
  // Read the register
  if (ReadRegisterBytes(reg_info, m_reg_data)) {
    const uint32_t reg = reg_info->kinds[eRegisterKindLLDB];
    if (m_reg_valid[reg] == false)
      return false;
    const bool partial_data_ok = false;
    Status error(value.SetValueFromData(
        reg_info, m_reg_data, reg_info->byte_offset, partial_data_ok));
    return error.Success();
  }
  return false;
}

bool GDBRemoteRegisterContext::PrivateSetRegisterValue(
    uint32_t reg, llvm::ArrayRef<uint8_t> data) {
  const RegisterInfo *reg_info = GetRegisterInfoAtIndex(reg);
  if (reg_info == nullptr)
    return false;

  // Invalidate if needed
  InvalidateIfNeeded(false);

  const size_t reg_byte_size = reg_info->byte_size;
  memcpy(const_cast<uint8_t *>(
             m_reg_data.PeekData(reg_info->byte_offset, reg_byte_size)),
         data.data(), std::min(data.size(), reg_byte_size));
  bool success = data.size() >= reg_byte_size;
  if (success) {
    SetRegisterIsValid(reg, true);
  } else if (data.size() > 0) {
    // Only set register is valid to false if we copied some bytes, else leave
    // it as it was.
    SetRegisterIsValid(reg, false);
  }
  return success;
}

bool GDBRemoteRegisterContext::PrivateSetRegisterValue(uint32_t reg,
                                                       uint64_t new_reg_val) {
  const RegisterInfo *reg_info = GetRegisterInfoAtIndex(reg);
  if (reg_info == nullptr)
    return false;

  // Early in process startup, we can get a thread that has an invalid byte
  // order because the process hasn't been completely set up yet (see the ctor
  // where the byte order is setfrom the process).  If that's the case, we
  // can't set the value here.
  if (m_reg_data.GetByteOrder() == eByteOrderInvalid) {
    return false;
  }

  // Invalidate if needed
  InvalidateIfNeeded(false);

  DataBufferSP buffer_sp(new DataBufferHeap(&new_reg_val, sizeof(new_reg_val)));
  DataExtractor data(buffer_sp, endian::InlHostByteOrder(), sizeof(void *));

  // If our register context and our register info disagree, which should never
  // happen, don't overwrite past the end of the buffer.
  if (m_reg_data.GetByteSize() < reg_info->byte_offset + reg_info->byte_size)
    return false;

  // Grab a pointer to where we are going to put this register
  uint8_t *dst = const_cast<uint8_t *>(
      m_reg_data.PeekData(reg_info->byte_offset, reg_info->byte_size));

  if (dst == nullptr)
    return false;

  if (data.CopyByteOrderedData(0,                          // src offset
                               reg_info->byte_size,        // src length
                               dst,                        // dst
                               reg_info->byte_size,        // dst length
                               m_reg_data.GetByteOrder())) // dst byte order
  {
    SetRegisterIsValid(reg, true);
    return true;
  }
  return false;
}

// Helper function for GDBRemoteRegisterContext::ReadRegisterBytes().
bool GDBRemoteRegisterContext::GetPrimordialRegister(
    const RegisterInfo *reg_info, GDBRemoteCommunicationClient &gdb_comm) {
  const uint32_t lldb_reg = reg_info->kinds[eRegisterKindLLDB];
  const uint32_t remote_reg = reg_info->kinds[eRegisterKindProcessPlugin];

  if (DataBufferSP buffer_sp =
          gdb_comm.ReadRegister(m_thread.GetProtocolID(), remote_reg))
    return PrivateSetRegisterValue(
        lldb_reg, llvm::ArrayRef<uint8_t>(buffer_sp->GetBytes(),
                                          buffer_sp->GetByteSize()));
  return false;
}

bool GDBRemoteRegisterContext::ReadRegisterBytes(const RegisterInfo *reg_info,
                                                 DataExtractor &data) {
  ExecutionContext exe_ctx(CalculateThread());

  Process *process = exe_ctx.GetProcessPtr();
  Thread *thread = exe_ctx.GetThreadPtr();
  if (process == nullptr || thread == nullptr)
    return false;

  GDBRemoteCommunicationClient &gdb_comm(
      ((ProcessGDBRemote *)process)->GetGDBRemote());

  InvalidateIfNeeded(false);

  const uint32_t reg = reg_info->kinds[eRegisterKindLLDB];

  if (!GetRegisterIsValid(reg)) {
    if (m_read_all_at_once && !m_gpacket_cached) {
      if (DataBufferSP buffer_sp =
              gdb_comm.ReadAllRegisters(m_thread.GetProtocolID())) {
        memcpy(const_cast<uint8_t *>(m_reg_data.GetDataStart()),
               buffer_sp->GetBytes(),
               std::min(buffer_sp->GetByteSize(), m_reg_data.GetByteSize()));
        if (buffer_sp->GetByteSize() >= m_reg_data.GetByteSize()) {
          SetAllRegisterValid(true);
          return true;
        } else if (buffer_sp->GetByteSize() > 0) {
          const int regcount = m_reg_info_sp->GetNumRegisters();
          for (int i = 0; i < regcount; i++) {
            struct RegisterInfo *reginfo =
                m_reg_info_sp->GetRegisterInfoAtIndex(i);
            if (reginfo->byte_offset + reginfo->byte_size <=
                buffer_sp->GetByteSize()) {
              m_reg_valid[i] = true;
            } else {
              m_reg_valid[i] = false;
            }
          }

          m_gpacket_cached = true;
          if (GetRegisterIsValid(reg))
            return true;
        } else {
          Log *log(ProcessGDBRemoteLog::GetLogIfAnyCategoryIsSet(GDBR_LOG_THREAD |
                                                                GDBR_LOG_PACKETS));
          LLDB_LOGF(
              log,
              "error: GDBRemoteRegisterContext::ReadRegisterBytes tried "
              "to read the "
              "entire register context at once, expected at least %" PRId64
              " bytes "
              "but only got %" PRId64 " bytes.",
              m_reg_data.GetByteSize(), buffer_sp->GetByteSize());
          return false;
        }
      }
    }
    if (reg_info->value_regs) {
      // Process this composite register request by delegating to the
      // constituent primordial registers.

      // Index of the primordial register.
      bool success = true;
      for (uint32_t idx = 0; success; ++idx) {
        const uint32_t prim_reg = reg_info->value_regs[idx];
        if (prim_reg == LLDB_INVALID_REGNUM)
          break;
        // We have a valid primordial register as our constituent. Grab the
        // corresponding register info.
        const RegisterInfo *prim_reg_info =
            GetRegisterInfo(eRegisterKindProcessPlugin, prim_reg);
        if (prim_reg_info == nullptr)
          success = false;
        else {
          // Read the containing register if it hasn't already been read
          if (!GetRegisterIsValid(prim_reg))
            success = GetPrimordialRegister(prim_reg_info, gdb_comm);
        }
      }

      if (success) {
        // If we reach this point, all primordial register requests have
        // succeeded. Validate this composite register.
        SetRegisterIsValid(reg_info, true);
      }
    } else {
      // Get each register individually
      GetPrimordialRegister(reg_info, gdb_comm);
    }

    // Make sure we got a valid register value after reading it
    if (!GetRegisterIsValid(reg))
      return false;
  }

  if (&data != &m_reg_data) {
    assert(m_reg_data.GetByteSize() >=
           reg_info->byte_offset + reg_info->byte_size);
    // If our register context and our register info disagree, which should
    // never happen, don't read past the end of the buffer.
    if (m_reg_data.GetByteSize() < reg_info->byte_offset + reg_info->byte_size)
      return false;

    // If we aren't extracting into our own buffer (which only happens when
    // this function is called from ReadRegisterValue(uint32_t, Scalar&)) then
    // we transfer bytes from our buffer into the data buffer that was passed
    // in

    data.SetByteOrder(m_reg_data.GetByteOrder());
    data.SetData(m_reg_data, reg_info->byte_offset, reg_info->byte_size);
  }
  return true;
}

bool GDBRemoteRegisterContext::WriteRegister(const RegisterInfo *reg_info,
                                             const RegisterValue &value) {
  DataExtractor data;
  if (value.GetData(data))
    return WriteRegisterBytes(reg_info, data, 0);
  return false;
}

// Helper function for GDBRemoteRegisterContext::WriteRegisterBytes().
bool GDBRemoteRegisterContext::SetPrimordialRegister(
    const RegisterInfo *reg_info, GDBRemoteCommunicationClient &gdb_comm) {
  StreamString packet;
  StringExtractorGDBRemote response;
  const uint32_t reg = reg_info->kinds[eRegisterKindLLDB];
  // Invalidate just this register
  SetRegisterIsValid(reg, false);

  return gdb_comm.WriteRegister(
      m_thread.GetProtocolID(), reg_info->kinds[eRegisterKindProcessPlugin],
      {m_reg_data.PeekData(reg_info->byte_offset, reg_info->byte_size),
       reg_info->byte_size});
}

bool GDBRemoteRegisterContext::WriteRegisterBytes(const RegisterInfo *reg_info,
                                                  DataExtractor &data,
                                                  uint32_t data_offset) {
  ExecutionContext exe_ctx(CalculateThread());

  Process *process = exe_ctx.GetProcessPtr();
  Thread *thread = exe_ctx.GetThreadPtr();
  if (process == nullptr || thread == nullptr)
    return false;

  GDBRemoteCommunicationClient &gdb_comm(
      ((ProcessGDBRemote *)process)->GetGDBRemote());

  assert(m_reg_data.GetByteSize() >=
         reg_info->byte_offset + reg_info->byte_size);

  // If our register context and our register info disagree, which should never
  // happen, don't overwrite past the end of the buffer.
  if (m_reg_data.GetByteSize() < reg_info->byte_offset + reg_info->byte_size)
    return false;

  // Grab a pointer to where we are going to put this register
  uint8_t *dst = const_cast<uint8_t *>(
      m_reg_data.PeekData(reg_info->byte_offset, reg_info->byte_size));

  if (dst == nullptr)
    return false;

  // Code below is specific to AArch64 target in SVE state
  // If vector granule (vg) register is being written then thread's
  // register context reconfiguration is triggered on success.
  bool do_reconfigure_arm64_sve = false;
  const ArchSpec &arch = process->GetTarget().GetArchitecture();
  if (arch.IsValid() && arch.GetTriple().isAArch64())
    if (strcmp(reg_info->name, "vg") == 0)
      do_reconfigure_arm64_sve = true;

  if (data.CopyByteOrderedData(data_offset,                // src offset
                               reg_info->byte_size,        // src length
                               dst,                        // dst
                               reg_info->byte_size,        // dst length
                               m_reg_data.GetByteOrder())) // dst byte order
  {
    GDBRemoteClientBase::Lock lock(gdb_comm, false);
    if (lock) {
      if (m_write_all_at_once) {
        // Invalidate all register values
        InvalidateIfNeeded(true);

        // Set all registers in one packet
        if (gdb_comm.WriteAllRegisters(
                m_thread.GetProtocolID(),
                {m_reg_data.GetDataStart(), size_t(m_reg_data.GetByteSize())}))

        {
          SetAllRegisterValid(false);

          if (do_reconfigure_arm64_sve)
            AArch64SVEReconfigure();

          return true;
        }
      } else {
        bool success = true;

        if (reg_info->value_regs) {
          // This register is part of another register. In this case we read
          // the actual register data for any "value_regs", and once all that
          // data is read, we will have enough data in our register context
          // bytes for the value of this register

          // Invalidate this composite register first.

          for (uint32_t idx = 0; success; ++idx) {
            const uint32_t reg = reg_info->value_regs[idx];
            if (reg == LLDB_INVALID_REGNUM)
              break;
            // We have a valid primordial register as our constituent. Grab the
            // corresponding register info.
            const RegisterInfo *value_reg_info =
                GetRegisterInfo(eRegisterKindProcessPlugin, reg);
            if (value_reg_info == nullptr)
              success = false;
            else
              success = SetPrimordialRegister(value_reg_info, gdb_comm);
          }
        } else {
          // This is an actual register, write it
          success = SetPrimordialRegister(reg_info, gdb_comm);

          if (success && do_reconfigure_arm64_sve)
            AArch64SVEReconfigure();
        }

        // Check if writing this register will invalidate any other register
        // values? If so, invalidate them
        if (reg_info->invalidate_regs) {
          for (uint32_t idx = 0, reg = reg_info->invalidate_regs[0];
               reg != LLDB_INVALID_REGNUM;
               reg = reg_info->invalidate_regs[++idx])
            SetRegisterIsValid(ConvertRegisterKindToRegisterNumber(
                                   eRegisterKindProcessPlugin, reg),
                               false);
        }

        return success;
      }
    } else {
      Log *log(ProcessGDBRemoteLog::GetLogIfAnyCategoryIsSet(GDBR_LOG_THREAD |
                                                             GDBR_LOG_PACKETS));
      if (log) {
        if (log->GetVerbose()) {
          StreamString strm;
          gdb_comm.DumpHistory(strm);
          LLDB_LOGF(log,
                    "error: failed to get packet sequence mutex, not sending "
                    "write register for \"%s\":\n%s",
                    reg_info->name, strm.GetData());
        } else
          LLDB_LOGF(log,
                    "error: failed to get packet sequence mutex, not sending "
                    "write register for \"%s\"",
                    reg_info->name);
      }
    }
  }
  return false;
}

bool GDBRemoteRegisterContext::ReadAllRegisterValues(
    RegisterCheckpoint &reg_checkpoint) {
  ExecutionContext exe_ctx(CalculateThread());

  Process *process = exe_ctx.GetProcessPtr();
  Thread *thread = exe_ctx.GetThreadPtr();
  if (process == nullptr || thread == nullptr)
    return false;

  GDBRemoteCommunicationClient &gdb_comm(
      ((ProcessGDBRemote *)process)->GetGDBRemote());

  uint32_t save_id = 0;
  if (gdb_comm.SaveRegisterState(thread->GetProtocolID(), save_id)) {
    reg_checkpoint.SetID(save_id);
    reg_checkpoint.GetData().reset();
    return true;
  } else {
    reg_checkpoint.SetID(0); // Invalid save ID is zero
    return ReadAllRegisterValues(reg_checkpoint.GetData());
  }
}

bool GDBRemoteRegisterContext::WriteAllRegisterValues(
    const RegisterCheckpoint &reg_checkpoint) {
  uint32_t save_id = reg_checkpoint.GetID();
  if (save_id != 0) {
    ExecutionContext exe_ctx(CalculateThread());

    Process *process = exe_ctx.GetProcessPtr();
    Thread *thread = exe_ctx.GetThreadPtr();
    if (process == nullptr || thread == nullptr)
      return false;

    GDBRemoteCommunicationClient &gdb_comm(
        ((ProcessGDBRemote *)process)->GetGDBRemote());

    return gdb_comm.RestoreRegisterState(m_thread.GetProtocolID(), save_id);
  } else {
    return WriteAllRegisterValues(reg_checkpoint.GetData());
  }
}

bool GDBRemoteRegisterContext::ReadAllRegisterValues(
    lldb::DataBufferSP &data_sp) {
  ExecutionContext exe_ctx(CalculateThread());

  Process *process = exe_ctx.GetProcessPtr();
  Thread *thread = exe_ctx.GetThreadPtr();
  if (process == nullptr || thread == nullptr)
    return false;

  GDBRemoteCommunicationClient &gdb_comm(
      ((ProcessGDBRemote *)process)->GetGDBRemote());

  const bool use_g_packet =
      !gdb_comm.AvoidGPackets((ProcessGDBRemote *)process);

  GDBRemoteClientBase::Lock lock(gdb_comm, false);
  if (lock) {
    if (gdb_comm.SyncThreadState(m_thread.GetProtocolID()))
      InvalidateAllRegisters();

    if (use_g_packet &&
        (data_sp = gdb_comm.ReadAllRegisters(m_thread.GetProtocolID())))
      return true;

    // We're going to read each register
    // individually and store them as binary data in a buffer.
    const RegisterInfo *reg_info;

    for (uint32_t i = 0; (reg_info = GetRegisterInfoAtIndex(i)) != nullptr;
         i++) {
      if (reg_info
              ->value_regs) // skip registers that are slices of real registers
        continue;
      ReadRegisterBytes(reg_info, m_reg_data);
      // ReadRegisterBytes saves the contents of the register in to the
      // m_reg_data buffer
    }
    data_sp = std::make_shared<DataBufferHeap>(
        m_reg_data.GetDataStart(), m_reg_info_sp->GetRegisterDataByteSize());
    return true;
  } else {

    Log *log(ProcessGDBRemoteLog::GetLogIfAnyCategoryIsSet(GDBR_LOG_THREAD |
                                                           GDBR_LOG_PACKETS));
    if (log) {
      if (log->GetVerbose()) {
        StreamString strm;
        gdb_comm.DumpHistory(strm);
        LLDB_LOGF(log,
                  "error: failed to get packet sequence mutex, not sending "
                  "read all registers:\n%s",
                  strm.GetData());
      } else
        LLDB_LOGF(log,
                  "error: failed to get packet sequence mutex, not sending "
                  "read all registers");
    }
  }

  data_sp.reset();
  return false;
}

bool GDBRemoteRegisterContext::WriteAllRegisterValues(
    const lldb::DataBufferSP &data_sp) {
  if (!data_sp || data_sp->GetBytes() == nullptr || data_sp->GetByteSize() == 0)
    return false;

  ExecutionContext exe_ctx(CalculateThread());

  Process *process = exe_ctx.GetProcessPtr();
  Thread *thread = exe_ctx.GetThreadPtr();
  if (process == nullptr || thread == nullptr)
    return false;

  GDBRemoteCommunicationClient &gdb_comm(
      ((ProcessGDBRemote *)process)->GetGDBRemote());

  const bool use_g_packet =
      !gdb_comm.AvoidGPackets((ProcessGDBRemote *)process);

  GDBRemoteClientBase::Lock lock(gdb_comm, false);
  if (lock) {
    // The data_sp contains the G response packet.
    if (use_g_packet) {
      if (gdb_comm.WriteAllRegisters(
              m_thread.GetProtocolID(),
              {data_sp->GetBytes(), size_t(data_sp->GetByteSize())}))
        return true;

      uint32_t num_restored = 0;
      // We need to manually go through all of the registers and restore them
      // manually
      DataExtractor restore_data(data_sp, m_reg_data.GetByteOrder(),
                                 m_reg_data.GetAddressByteSize());

      const RegisterInfo *reg_info;

      // The g packet contents may either include the slice registers
      // (registers defined in terms of other registers, e.g. eax is a subset
      // of rax) or not.  The slice registers should NOT be in the g packet,
      // but some implementations may incorrectly include them.
      //
      // If the slice registers are included in the packet, we must step over
      // the slice registers when parsing the packet -- relying on the
      // RegisterInfo byte_offset field would be incorrect. If the slice
      // registers are not included, then using the byte_offset values into the
      // data buffer is the best way to find individual register values.

      uint64_t size_including_slice_registers = 0;
      uint64_t size_not_including_slice_registers = 0;
      uint64_t size_by_highest_offset = 0;

      for (uint32_t reg_idx = 0;
           (reg_info = GetRegisterInfoAtIndex(reg_idx)) != nullptr; ++reg_idx) {
        size_including_slice_registers += reg_info->byte_size;
        if (reg_info->value_regs == nullptr)
          size_not_including_slice_registers += reg_info->byte_size;
        if (reg_info->byte_offset >= size_by_highest_offset)
          size_by_highest_offset = reg_info->byte_offset + reg_info->byte_size;
      }

      bool use_byte_offset_into_buffer;
      if (size_by_highest_offset == restore_data.GetByteSize()) {
        // The size of the packet agrees with the highest offset: + size in the
        // register file
        use_byte_offset_into_buffer = true;
      } else if (size_not_including_slice_registers ==
                 restore_data.GetByteSize()) {
        // The size of the packet is the same as concatenating all of the
        // registers sequentially, skipping the slice registers
        use_byte_offset_into_buffer = true;
      } else if (size_including_slice_registers == restore_data.GetByteSize()) {
        // The slice registers are present in the packet (when they shouldn't
        // be). Don't try to use the RegisterInfo byte_offset into the
        // restore_data, it will point to the wrong place.
        use_byte_offset_into_buffer = false;
      } else {
        // None of our expected sizes match the actual g packet data we're
        // looking at. The most conservative approach here is to use the
        // running total byte offset.
        use_byte_offset_into_buffer = false;
      }

      // In case our register definitions don't include the correct offsets,
      // keep track of the size of each reg & compute offset based on that.
      uint32_t running_byte_offset = 0;
      for (uint32_t reg_idx = 0;
           (reg_info = GetRegisterInfoAtIndex(reg_idx)) != nullptr;
           ++reg_idx, running_byte_offset += reg_info->byte_size) {
        // Skip composite aka slice registers (e.g. eax is a slice of rax).
        if (reg_info->value_regs)
          continue;

        const uint32_t reg = reg_info->kinds[eRegisterKindLLDB];

        uint32_t register_offset;
        if (use_byte_offset_into_buffer) {
          register_offset = reg_info->byte_offset;
        } else {
          register_offset = running_byte_offset;
        }

        const uint32_t reg_byte_size = reg_info->byte_size;

        const uint8_t *restore_src =
            restore_data.PeekData(register_offset, reg_byte_size);
        if (restore_src) {
          SetRegisterIsValid(reg, false);
          if (gdb_comm.WriteRegister(
                  m_thread.GetProtocolID(),
                  reg_info->kinds[eRegisterKindProcessPlugin],
                  {restore_src, reg_byte_size}))
            ++num_restored;
        }
      }
      return num_restored > 0;
    } else {
      // For the use_g_packet == false case, we're going to write each register
      // individually.  The data buffer is binary data in this case, instead of
      // ascii characters.

      bool arm64_debugserver = false;
      if (m_thread.GetProcess().get()) {
        const ArchSpec &arch =
            m_thread.GetProcess()->GetTarget().GetArchitecture();
        if (arch.IsValid() && (arch.GetMachine() == llvm::Triple::aarch64 ||
                               arch.GetMachine() == llvm::Triple::aarch64_32) &&
            arch.GetTriple().getVendor() == llvm::Triple::Apple &&
            arch.GetTriple().getOS() == llvm::Triple::IOS) {
          arm64_debugserver = true;
        }
      }
      uint32_t num_restored = 0;
      const RegisterInfo *reg_info;
      for (uint32_t i = 0; (reg_info = GetRegisterInfoAtIndex(i)) != nullptr;
           i++) {
        if (reg_info->value_regs) // skip registers that are slices of real
                                  // registers
          continue;
        // Skip the fpsr and fpcr floating point status/control register
        // writing to work around a bug in an older version of debugserver that
        // would lead to register context corruption when writing fpsr/fpcr.
        if (arm64_debugserver && (strcmp(reg_info->name, "fpsr") == 0 ||
                                  strcmp(reg_info->name, "fpcr") == 0)) {
          continue;
        }

        SetRegisterIsValid(reg_info, false);
        if (gdb_comm.WriteRegister(m_thread.GetProtocolID(),
                                   reg_info->kinds[eRegisterKindProcessPlugin],
                                   {data_sp->GetBytes() + reg_info->byte_offset,
                                    reg_info->byte_size}))
          ++num_restored;
      }
      return num_restored > 0;
    }
  } else {
    Log *log(ProcessGDBRemoteLog::GetLogIfAnyCategoryIsSet(GDBR_LOG_THREAD |
                                                           GDBR_LOG_PACKETS));
    if (log) {
      if (log->GetVerbose()) {
        StreamString strm;
        gdb_comm.DumpHistory(strm);
        LLDB_LOGF(log,
                  "error: failed to get packet sequence mutex, not sending "
                  "write all registers:\n%s",
                  strm.GetData());
      } else
        LLDB_LOGF(log,
                  "error: failed to get packet sequence mutex, not sending "
                  "write all registers");
    }
  }
  return false;
}

uint32_t GDBRemoteRegisterContext::ConvertRegisterKindToRegisterNumber(
    lldb::RegisterKind kind, uint32_t num) {
  return m_reg_info_sp->ConvertRegisterKindToRegisterNumber(kind, num);
}

bool GDBRemoteRegisterContext::AArch64SVEReconfigure() {
  if (!m_reg_info_sp)
    return false;

  const RegisterInfo *reg_info = m_reg_info_sp->GetRegisterInfo("vg");
  if (!reg_info)
    return false;

  uint64_t fail_value = LLDB_INVALID_ADDRESS;
  uint32_t vg_reg_num = reg_info->kinds[eRegisterKindLLDB];
  uint64_t vg_reg_value = ReadRegisterAsUnsigned(vg_reg_num, fail_value);

  if (vg_reg_value != fail_value && vg_reg_value <= 32) {
    const RegisterInfo *reg_info = m_reg_info_sp->GetRegisterInfo("p0");
    if (!reg_info || vg_reg_value == reg_info->byte_size)
      return false;

    if (m_reg_info_sp->UpdateARM64SVERegistersInfos(vg_reg_value)) {
      // Make a heap based buffer that is big enough to store all registers
      m_reg_data.SetData(std::make_shared<DataBufferHeap>(
          m_reg_info_sp->GetRegisterDataByteSize(), 0));
      m_reg_data.SetByteOrder(GetByteOrder());

      InvalidateAllRegisters();

      return true;
    }
  }

  return false;
}

bool GDBRemoteDynamicRegisterInfo::UpdateARM64SVERegistersInfos(uint64_t vg) {
  // SVE Z register size is vg x 8 bytes.
  uint32_t z_reg_byte_size = vg * 8;

  // SVE vector length has changed, accordingly set size of Z, P and FFR
  // registers. Also invalidate register offsets it will be recalculated
  // after SVE register size update.
  for (auto &reg : m_regs) {
    if (reg.value_regs == nullptr) {
      if (reg.name[0] == 'z' && isdigit(reg.name[1]))
        reg.byte_size = z_reg_byte_size;
      else if (reg.name[0] == 'p' && isdigit(reg.name[1]))
        reg.byte_size = vg;
      else if (strcmp(reg.name, "ffr") == 0)
        reg.byte_size = vg;
    }
    reg.byte_offset = LLDB_INVALID_INDEX32;
  }

  // Re-calculate register offsets
  ConfigureOffsets();
  return true;
}

void GDBRemoteDynamicRegisterInfo::HardcodeARMRegisters(bool from_scratch) {
  // For Advanced SIMD and VFP register mapping.
  static uint32_t g_d0_regs[] = {26, 27, LLDB_INVALID_REGNUM};  // (s0, s1)
  static uint32_t g_d1_regs[] = {28, 29, LLDB_INVALID_REGNUM};  // (s2, s3)
  static uint32_t g_d2_regs[] = {30, 31, LLDB_INVALID_REGNUM};  // (s4, s5)
  static uint32_t g_d3_regs[] = {32, 33, LLDB_INVALID_REGNUM};  // (s6, s7)
  static uint32_t g_d4_regs[] = {34, 35, LLDB_INVALID_REGNUM};  // (s8, s9)
  static uint32_t g_d5_regs[] = {36, 37, LLDB_INVALID_REGNUM};  // (s10, s11)
  static uint32_t g_d6_regs[] = {38, 39, LLDB_INVALID_REGNUM};  // (s12, s13)
  static uint32_t g_d7_regs[] = {40, 41, LLDB_INVALID_REGNUM};  // (s14, s15)
  static uint32_t g_d8_regs[] = {42, 43, LLDB_INVALID_REGNUM};  // (s16, s17)
  static uint32_t g_d9_regs[] = {44, 45, LLDB_INVALID_REGNUM};  // (s18, s19)
  static uint32_t g_d10_regs[] = {46, 47, LLDB_INVALID_REGNUM}; // (s20, s21)
  static uint32_t g_d11_regs[] = {48, 49, LLDB_INVALID_REGNUM}; // (s22, s23)
  static uint32_t g_d12_regs[] = {50, 51, LLDB_INVALID_REGNUM}; // (s24, s25)
  static uint32_t g_d13_regs[] = {52, 53, LLDB_INVALID_REGNUM}; // (s26, s27)
  static uint32_t g_d14_regs[] = {54, 55, LLDB_INVALID_REGNUM}; // (s28, s29)
  static uint32_t g_d15_regs[] = {56, 57, LLDB_INVALID_REGNUM}; // (s30, s31)
  static uint32_t g_q0_regs[] = {
      26, 27, 28, 29, LLDB_INVALID_REGNUM}; // (d0, d1) -> (s0, s1, s2, s3)
  static uint32_t g_q1_regs[] = {
      30, 31, 32, 33, LLDB_INVALID_REGNUM}; // (d2, d3) -> (s4, s5, s6, s7)
  static uint32_t g_q2_regs[] = {
      34, 35, 36, 37, LLDB_INVALID_REGNUM}; // (d4, d5) -> (s8, s9, s10, s11)
  static uint32_t g_q3_regs[] = {
      38, 39, 40, 41, LLDB_INVALID_REGNUM}; // (d6, d7) -> (s12, s13, s14, s15)
  static uint32_t g_q4_regs[] = {
      42, 43, 44, 45, LLDB_INVALID_REGNUM}; // (d8, d9) -> (s16, s17, s18, s19)
  static uint32_t g_q5_regs[] = {
      46, 47, 48, 49,
      LLDB_INVALID_REGNUM}; // (d10, d11) -> (s20, s21, s22, s23)
  static uint32_t g_q6_regs[] = {
      50, 51, 52, 53,
      LLDB_INVALID_REGNUM}; // (d12, d13) -> (s24, s25, s26, s27)
  static uint32_t g_q7_regs[] = {
      54, 55, 56, 57,
      LLDB_INVALID_REGNUM}; // (d14, d15) -> (s28, s29, s30, s31)
  static uint32_t g_q8_regs[] = {59, 60, LLDB_INVALID_REGNUM};  // (d16, d17)
  static uint32_t g_q9_regs[] = {61, 62, LLDB_INVALID_REGNUM};  // (d18, d19)
  static uint32_t g_q10_regs[] = {63, 64, LLDB_INVALID_REGNUM}; // (d20, d21)
  static uint32_t g_q11_regs[] = {65, 66, LLDB_INVALID_REGNUM}; // (d22, d23)
  static uint32_t g_q12_regs[] = {67, 68, LLDB_INVALID_REGNUM}; // (d24, d25)
  static uint32_t g_q13_regs[] = {69, 70, LLDB_INVALID_REGNUM}; // (d26, d27)
  static uint32_t g_q14_regs[] = {71, 72, LLDB_INVALID_REGNUM}; // (d28, d29)
  static uint32_t g_q15_regs[] = {73, 74, LLDB_INVALID_REGNUM}; // (d30, d31)

  // This is our array of composite registers, with each element coming from
  // the above register mappings.
  static uint32_t *g_composites[] = {
      g_d0_regs,  g_d1_regs,  g_d2_regs,  g_d3_regs,  g_d4_regs,  g_d5_regs,
      g_d6_regs,  g_d7_regs,  g_d8_regs,  g_d9_regs,  g_d10_regs, g_d11_regs,
      g_d12_regs, g_d13_regs, g_d14_regs, g_d15_regs, g_q0_regs,  g_q1_regs,
      g_q2_regs,  g_q3_regs,  g_q4_regs,  g_q5_regs,  g_q6_regs,  g_q7_regs,
      g_q8_regs,  g_q9_regs,  g_q10_regs, g_q11_regs, g_q12_regs, g_q13_regs,
      g_q14_regs, g_q15_regs};

  // clang-format off
    static RegisterInfo g_register_infos[] = {
//   NAME     ALT     SZ   OFF  ENCODING          FORMAT          EH_FRAME             DWARF                GENERIC                 PROCESS PLUGIN  LLDB    VALUE REGS    INVALIDATE REGS SIZE EXPR SIZE LEN
//   ======   ======  ===  ===  =============     ==========      ===================  ===================  ======================  =============   ====    ==========    =============== ========= ========
    { "r0",   "arg1",   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r0,          dwarf_r0,            LLDB_REGNUM_GENERIC_ARG1,0,               0 },     nullptr,           nullptr,  nullptr,       0 },
    { "r1",   "arg2",   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r1,          dwarf_r1,            LLDB_REGNUM_GENERIC_ARG2,1,               1 },     nullptr,           nullptr,  nullptr,       0 },
    { "r2",   "arg3",   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r2,          dwarf_r2,            LLDB_REGNUM_GENERIC_ARG3,2,               2 },     nullptr,           nullptr,  nullptr,       0 },
    { "r3",   "arg4",   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r3,          dwarf_r3,            LLDB_REGNUM_GENERIC_ARG4,3,               3 },     nullptr,           nullptr,  nullptr,       0 },
    { "r4",  nullptr,   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r4,          dwarf_r4,            LLDB_INVALID_REGNUM,     4,               4 },     nullptr,           nullptr,  nullptr,       0 },
    { "r5",  nullptr,   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r5,          dwarf_r5,            LLDB_INVALID_REGNUM,     5,               5 },     nullptr,           nullptr,  nullptr,       0 },
    { "r6",  nullptr,   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r6,          dwarf_r6,            LLDB_INVALID_REGNUM,     6,               6 },     nullptr,           nullptr,  nullptr,       0 },
    { "r7",     "fp",   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r7,          dwarf_r7,            LLDB_REGNUM_GENERIC_FP,  7,               7 },     nullptr,           nullptr,  nullptr,       0 },
    { "r8",  nullptr,   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r8,          dwarf_r8,            LLDB_INVALID_REGNUM,     8,               8 },     nullptr,           nullptr,  nullptr,       0 },
    { "r9",  nullptr,   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r9,          dwarf_r9,            LLDB_INVALID_REGNUM,     9,               9 },     nullptr,           nullptr,  nullptr,       0 },
    { "r10", nullptr,   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r10,         dwarf_r10,           LLDB_INVALID_REGNUM,    10,              10 },     nullptr,           nullptr,  nullptr,       0 },
    { "r11", nullptr,   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r11,         dwarf_r11,           LLDB_INVALID_REGNUM,    11,              11 },     nullptr,           nullptr,  nullptr,       0 },
    { "r12", nullptr,   4,   0, eEncodingUint,    eFormatHex,   { ehframe_r12,         dwarf_r12,           LLDB_INVALID_REGNUM,    12,              12 },     nullptr,           nullptr,  nullptr,       0 },
    { "sp",     "r13",  4,   0, eEncodingUint,    eFormatHex,   { ehframe_sp,          dwarf_sp,            LLDB_REGNUM_GENERIC_SP, 13,              13 },     nullptr,           nullptr,  nullptr,       0 },
    { "lr",     "r14",  4,   0, eEncodingUint,    eFormatHex,   { ehframe_lr,          dwarf_lr,            LLDB_REGNUM_GENERIC_RA, 14,              14 },     nullptr,           nullptr,  nullptr,       0 },
    { "pc",     "r15",  4,   0, eEncodingUint,    eFormatHex,   { ehframe_pc,          dwarf_pc,            LLDB_REGNUM_GENERIC_PC, 15,              15 },     nullptr,           nullptr,  nullptr,       0 },
    { "f0",  nullptr,  12,   0, eEncodingUint,    eFormatHex,   { LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM,    16,              16 },     nullptr,           nullptr,  nullptr,       0 },
    { "f1",  nullptr,  12,   0, eEncodingUint,    eFormatHex,   { LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM,    17,              17 },     nullptr,           nullptr,  nullptr,       0 },
    { "f2",  nullptr,  12,   0, eEncodingUint,    eFormatHex,   { LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM,    18,              18 },     nullptr,           nullptr,  nullptr,       0 },
    { "f3",  nullptr,  12,   0, eEncodingUint,    eFormatHex,   { LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM,    19,              19 },     nullptr,           nullptr,  nullptr,       0 },
    { "f4",  nullptr,  12,   0, eEncodingUint,    eFormatHex,   { LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM,    20,              20 },     nullptr,           nullptr,  nullptr,       0 },
    { "f5",  nullptr,  12,   0, eEncodingUint,    eFormatHex,   { LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM,    21,              21 },     nullptr,           nullptr,  nullptr,       0 },
    { "f6",  nullptr,  12,   0, eEncodingUint,    eFormatHex,   { LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM,    22,              22 },     nullptr,           nullptr,  nullptr,       0 },
    { "f7",  nullptr,  12,   0, eEncodingUint,    eFormatHex,   { LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM,    23,              23 },     nullptr,           nullptr,  nullptr,       0 },
    { "fps", nullptr,   4,   0, eEncodingUint,    eFormatHex,   { LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM,    24,              24 },     nullptr,           nullptr,  nullptr,       0 },
    { "cpsr","flags",   4,   0, eEncodingUint,    eFormatHex,   { ehframe_cpsr,        dwarf_cpsr,          LLDB_INVALID_REGNUM,    25,              25 },     nullptr,           nullptr,  nullptr,       0 },
    { "s0",  nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s0,            LLDB_INVALID_REGNUM,    26,              26 },     nullptr,           nullptr,  nullptr,       0 },
    { "s1",  nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s1,            LLDB_INVALID_REGNUM,    27,              27 },     nullptr,           nullptr,  nullptr,       0 },
    { "s2",  nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s2,            LLDB_INVALID_REGNUM,    28,              28 },     nullptr,           nullptr,  nullptr,       0 },
    { "s3",  nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s3,            LLDB_INVALID_REGNUM,    29,              29 },     nullptr,           nullptr,  nullptr,       0 },
    { "s4",  nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s4,            LLDB_INVALID_REGNUM,    30,              30 },     nullptr,           nullptr,  nullptr,       0 },
    { "s5",  nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s5,            LLDB_INVALID_REGNUM,    31,              31 },     nullptr,           nullptr,  nullptr,       0 },
    { "s6",  nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s6,            LLDB_INVALID_REGNUM,    32,              32 },     nullptr,           nullptr,  nullptr,       0 },
    { "s7",  nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s7,            LLDB_INVALID_REGNUM,    33,              33 },     nullptr,           nullptr,  nullptr,       0 },
    { "s8",  nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s8,            LLDB_INVALID_REGNUM,    34,              34 },     nullptr,           nullptr,  nullptr,       0 },
    { "s9",  nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s9,            LLDB_INVALID_REGNUM,    35,              35 },     nullptr,           nullptr,  nullptr,       0 },
    { "s10", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s10,           LLDB_INVALID_REGNUM,    36,              36 },     nullptr,           nullptr,  nullptr,       0 },
    { "s11", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s11,           LLDB_INVALID_REGNUM,    37,              37 },     nullptr,           nullptr,  nullptr,       0 },
    { "s12", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s12,           LLDB_INVALID_REGNUM,    38,              38 },     nullptr,           nullptr,  nullptr,       0 },
    { "s13", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s13,           LLDB_INVALID_REGNUM,    39,              39 },     nullptr,           nullptr,  nullptr,       0 },
    { "s14", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s14,           LLDB_INVALID_REGNUM,    40,              40 },     nullptr,           nullptr,  nullptr,       0 },
    { "s15", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s15,           LLDB_INVALID_REGNUM,    41,              41 },     nullptr,           nullptr,  nullptr,       0 },
    { "s16", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s16,           LLDB_INVALID_REGNUM,    42,              42 },     nullptr,           nullptr,  nullptr,       0 },
    { "s17", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s17,           LLDB_INVALID_REGNUM,    43,              43 },     nullptr,           nullptr,  nullptr,       0 },
    { "s18", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s18,           LLDB_INVALID_REGNUM,    44,              44 },     nullptr,           nullptr,  nullptr,       0 },
    { "s19", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s19,           LLDB_INVALID_REGNUM,    45,              45 },     nullptr,           nullptr,  nullptr,       0 },
    { "s20", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s20,           LLDB_INVALID_REGNUM,    46,              46 },     nullptr,           nullptr,  nullptr,       0 },
    { "s21", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s21,           LLDB_INVALID_REGNUM,    47,              47 },     nullptr,           nullptr,  nullptr,       0 },
    { "s22", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s22,           LLDB_INVALID_REGNUM,    48,              48 },     nullptr,           nullptr,  nullptr,       0 },
    { "s23", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s23,           LLDB_INVALID_REGNUM,    49,              49 },     nullptr,           nullptr,  nullptr,       0 },
    { "s24", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s24,           LLDB_INVALID_REGNUM,    50,              50 },     nullptr,           nullptr,  nullptr,       0 },
    { "s25", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s25,           LLDB_INVALID_REGNUM,    51,              51 },     nullptr,           nullptr,  nullptr,       0 },
    { "s26", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s26,           LLDB_INVALID_REGNUM,    52,              52 },     nullptr,           nullptr,  nullptr,       0 },
    { "s27", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s27,           LLDB_INVALID_REGNUM,    53,              53 },     nullptr,           nullptr,  nullptr,       0 },
    { "s28", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s28,           LLDB_INVALID_REGNUM,    54,              54 },     nullptr,           nullptr,  nullptr,       0 },
    { "s29", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s29,           LLDB_INVALID_REGNUM,    55,              55 },     nullptr,           nullptr,  nullptr,       0 },
    { "s30", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s30,           LLDB_INVALID_REGNUM,    56,              56 },     nullptr,           nullptr,  nullptr,       0 },
    { "s31", nullptr,   4,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_s31,           LLDB_INVALID_REGNUM,    57,              57 },     nullptr,           nullptr,  nullptr,       0 },
    { "fpscr",nullptr,  4,   0, eEncodingUint,    eFormatHex,   { LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM,    58,              58 },     nullptr,           nullptr,  nullptr,       0 },
    { "d16", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d16,           LLDB_INVALID_REGNUM,    59,              59 },     nullptr,           nullptr,  nullptr,       0 },
    { "d17", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d17,           LLDB_INVALID_REGNUM,    60,              60 },     nullptr,           nullptr,  nullptr,       0 },
    { "d18", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d18,           LLDB_INVALID_REGNUM,    61,              61 },     nullptr,           nullptr,  nullptr,       0 },
    { "d19", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d19,           LLDB_INVALID_REGNUM,    62,              62 },     nullptr,           nullptr,  nullptr,       0 },
    { "d20", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d20,           LLDB_INVALID_REGNUM,    63,              63 },     nullptr,           nullptr,  nullptr,       0 },
    { "d21", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d21,           LLDB_INVALID_REGNUM,    64,              64 },     nullptr,           nullptr,  nullptr,       0 },
    { "d22", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d22,           LLDB_INVALID_REGNUM,    65,              65 },     nullptr,           nullptr,  nullptr,       0 },
    { "d23", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d23,           LLDB_INVALID_REGNUM,    66,              66 },     nullptr,           nullptr,  nullptr,       0 },
    { "d24", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d24,           LLDB_INVALID_REGNUM,    67,              67 },     nullptr,           nullptr,  nullptr,       0 },
    { "d25", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d25,           LLDB_INVALID_REGNUM,    68,              68 },     nullptr,           nullptr,  nullptr,       0 },
    { "d26", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d26,           LLDB_INVALID_REGNUM,    69,              69 },     nullptr,           nullptr,  nullptr,       0 },
    { "d27", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d27,           LLDB_INVALID_REGNUM,    70,              70 },     nullptr,           nullptr,  nullptr,       0 },
    { "d28", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d28,           LLDB_INVALID_REGNUM,    71,              71 },     nullptr,           nullptr,  nullptr,       0 },
    { "d29", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d29,           LLDB_INVALID_REGNUM,    72,              72 },     nullptr,           nullptr,  nullptr,       0 },
    { "d30", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d30,           LLDB_INVALID_REGNUM,    73,              73 },     nullptr,           nullptr,  nullptr,       0 },
    { "d31", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d31,           LLDB_INVALID_REGNUM,    74,              74 },     nullptr,           nullptr,  nullptr,       0 },
    { "d0",  nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d0,            LLDB_INVALID_REGNUM,    75,              75 },   g_d0_regs,           nullptr,  nullptr,       0 },
    { "d1",  nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d1,            LLDB_INVALID_REGNUM,    76,              76 },   g_d1_regs,           nullptr,  nullptr,       0 },
    { "d2",  nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d2,            LLDB_INVALID_REGNUM,    77,              77 },   g_d2_regs,           nullptr,  nullptr,       0 },
    { "d3",  nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d3,            LLDB_INVALID_REGNUM,    78,              78 },   g_d3_regs,           nullptr,  nullptr,       0 },
    { "d4",  nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d4,            LLDB_INVALID_REGNUM,    79,              79 },   g_d4_regs,           nullptr,  nullptr,       0 },
    { "d5",  nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d5,            LLDB_INVALID_REGNUM,    80,              80 },   g_d5_regs,           nullptr,  nullptr,       0 },
    { "d6",  nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d6,            LLDB_INVALID_REGNUM,    81,              81 },   g_d6_regs,           nullptr,  nullptr,       0 },
    { "d7",  nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d7,            LLDB_INVALID_REGNUM,    82,              82 },   g_d7_regs,           nullptr,  nullptr,       0 },
    { "d8",  nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d8,            LLDB_INVALID_REGNUM,    83,              83 },   g_d8_regs,           nullptr,  nullptr,       0 },
    { "d9",  nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d9,            LLDB_INVALID_REGNUM,    84,              84 },   g_d9_regs,           nullptr,  nullptr,       0 },
    { "d10", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d10,           LLDB_INVALID_REGNUM,    85,              85 },  g_d10_regs,           nullptr,  nullptr,       0 },
    { "d11", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d11,           LLDB_INVALID_REGNUM,    86,              86 },  g_d11_regs,           nullptr,  nullptr,       0 },
    { "d12", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d12,           LLDB_INVALID_REGNUM,    87,              87 },  g_d12_regs,           nullptr,  nullptr,       0 },
    { "d13", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d13,           LLDB_INVALID_REGNUM,    88,              88 },  g_d13_regs,           nullptr,  nullptr,       0 },
    { "d14", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d14,           LLDB_INVALID_REGNUM,    89,              89 },  g_d14_regs,           nullptr,  nullptr,       0 },
    { "d15", nullptr,   8,   0, eEncodingIEEE754, eFormatFloat, { LLDB_INVALID_REGNUM, dwarf_d15,           LLDB_INVALID_REGNUM,    90,              90 },  g_d15_regs,           nullptr,  nullptr,       0 },
    { "q0",  nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q0,    LLDB_INVALID_REGNUM,    91,              91 },   g_q0_regs,           nullptr,  nullptr,       0 },
    { "q1",  nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q1,    LLDB_INVALID_REGNUM,    92,              92 },   g_q1_regs,           nullptr,  nullptr,       0 },
    { "q2",  nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q2,    LLDB_INVALID_REGNUM,    93,              93 },   g_q2_regs,           nullptr,  nullptr,       0 },
    { "q3",  nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q3,    LLDB_INVALID_REGNUM,    94,              94 },   g_q3_regs,           nullptr,  nullptr,       0 },
    { "q4",  nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q4,    LLDB_INVALID_REGNUM,    95,              95 },   g_q4_regs,           nullptr,  nullptr,       0 },
    { "q5",  nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q5,    LLDB_INVALID_REGNUM,    96,              96 },   g_q5_regs,           nullptr,  nullptr,       0 },
    { "q6",  nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q6,    LLDB_INVALID_REGNUM,    97,              97 },   g_q6_regs,           nullptr,  nullptr,       0 },
    { "q7",  nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q7,    LLDB_INVALID_REGNUM,    98,              98 },   g_q7_regs,           nullptr,  nullptr,       0 },
    { "q8",  nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q8,    LLDB_INVALID_REGNUM,    99,              99 },   g_q8_regs,           nullptr,  nullptr,       0 },
    { "q9",  nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q9,    LLDB_INVALID_REGNUM,   100,             100 },   g_q9_regs,           nullptr,  nullptr,       0 },
    { "q10", nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q10,   LLDB_INVALID_REGNUM,   101,             101 },  g_q10_regs,           nullptr,  nullptr,       0 },
    { "q11", nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q11,   LLDB_INVALID_REGNUM,   102,             102 },  g_q11_regs,           nullptr,  nullptr,       0 },
    { "q12", nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q12,   LLDB_INVALID_REGNUM,   103,             103 },  g_q12_regs,           nullptr,  nullptr,       0 },
    { "q13", nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q13,   LLDB_INVALID_REGNUM,   104,             104 },  g_q13_regs,           nullptr,  nullptr,       0 },
    { "q14", nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q14,   LLDB_INVALID_REGNUM,   105,             105 },  g_q14_regs,           nullptr,  nullptr,       0 },
    { "q15", nullptr,   16,  0, eEncodingVector,  eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_q15,   LLDB_INVALID_REGNUM,   106,             106 },  g_q15_regs,           nullptr,  nullptr,       0 }
    };
  // clang-format on

  static const uint32_t num_registers = llvm::array_lengthof(g_register_infos);
  static ConstString gpr_reg_set("General Purpose Registers");
  static ConstString sfp_reg_set("Software Floating Point Registers");
  static ConstString vfp_reg_set("Floating Point Registers");
  size_t i;
  if (from_scratch) {
    // Calculate the offsets of the registers
    // Note that the layout of the "composite" registers (d0-d15 and q0-q15)
    // which comes after the "primordial" registers is important.  This enables
    // us to calculate the offset of the composite register by using the offset
    // of its first primordial register.  For example, to calculate the offset
    // of q0, use s0's offset.
    if (g_register_infos[2].byte_offset == 0) {
      uint32_t byte_offset = 0;
      for (i = 0; i < num_registers; ++i) {
        // For primordial registers, increment the byte_offset by the byte_size
        // to arrive at the byte_offset for the next register.  Otherwise, we
        // have a composite register whose offset can be calculated by
        // consulting the offset of its first primordial register.
        if (!g_register_infos[i].value_regs) {
          g_register_infos[i].byte_offset = byte_offset;
          byte_offset += g_register_infos[i].byte_size;
        } else {
          const uint32_t first_primordial_reg =
              g_register_infos[i].value_regs[0];
          g_register_infos[i].byte_offset =
              g_register_infos[first_primordial_reg].byte_offset;
        }
      }
    }
    for (i = 0; i < num_registers; ++i) {
      ConstString name;
      ConstString alt_name;
      if (g_register_infos[i].name && g_register_infos[i].name[0])
        name.SetCString(g_register_infos[i].name);
      if (g_register_infos[i].alt_name && g_register_infos[i].alt_name[0])
        alt_name.SetCString(g_register_infos[i].alt_name);

      if (i <= 15 || i == 25)
        AddRegister(g_register_infos[i], name, alt_name, gpr_reg_set);
      else if (i <= 24)
        AddRegister(g_register_infos[i], name, alt_name, sfp_reg_set);
      else
        AddRegister(g_register_infos[i], name, alt_name, vfp_reg_set);
    }
  } else {
    // Add composite registers to our primordial registers, then.
    const size_t num_composites = llvm::array_lengthof(g_composites);
    const size_t num_dynamic_regs = GetNumRegisters();
    const size_t num_common_regs = num_registers - num_composites;
    RegisterInfo *g_comp_register_infos = g_register_infos + num_common_regs;

    // First we need to validate that all registers that we already have match
    // the non composite regs. If so, then we can add the registers, else we
    // need to bail
    bool match = true;
    if (num_dynamic_regs == num_common_regs) {
      for (i = 0; match && i < num_dynamic_regs; ++i) {
        // Make sure all register names match
        if (m_regs[i].name && g_register_infos[i].name) {
          if (strcmp(m_regs[i].name, g_register_infos[i].name)) {
            match = false;
            break;
          }
        }

        // Make sure all register byte sizes match
        if (m_regs[i].byte_size != g_register_infos[i].byte_size) {
          match = false;
          break;
        }
      }
    } else {
      // Wrong number of registers.
      match = false;
    }
    // If "match" is true, then we can add extra registers.
    if (match) {
      for (i = 0; i < num_composites; ++i) {
        ConstString name;
        ConstString alt_name;
        const uint32_t first_primordial_reg =
            g_comp_register_infos[i].value_regs[0];
        const char *reg_name = g_register_infos[first_primordial_reg].name;
        if (reg_name && reg_name[0]) {
          for (uint32_t j = 0; j < num_dynamic_regs; ++j) {
            const RegisterInfo *reg_info = GetRegisterInfoAtIndex(j);
            // Find a matching primordial register info entry.
            if (reg_info && reg_info->name &&
                ::strcasecmp(reg_info->name, reg_name) == 0) {
              // The name matches the existing primordial entry. Find and
              // assign the offset, and then add this composite register entry.
              g_comp_register_infos[i].byte_offset = reg_info->byte_offset;
              name.SetCString(g_comp_register_infos[i].name);
              AddRegister(g_comp_register_infos[i], name, alt_name,
                          vfp_reg_set);
            }
          }
        }
      }
    }
  }
}